#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=2e5+1000;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
class Solution {
public:
    vector<vector<int>> construct2DArray(vector<int>& original, int m, int n) {
            if(original.size()!=n*m) return vector<vector<int>>();
            int tot=0;
            vector<vector<int>>ans;
            for(int i=0;i<original.size();i++){
                vector<int>res;
                res.push_back(original[i]);
                tot++;
                if(tot==n){
                    tot=0;
                    ans.push_back(res);
                }
            }
            return ans;
    }
};
int main(void){
   	cin.tie(0);std::ios::sync_with_stdio(false);

   	return 0;
}
